Methods and systems for ultrasound delivery through a cranial aperture

Abstract

A method for delivering ultrasound energy to a patient's intracranial space includes forming at least one aperture in the patient's skull, introducing at least one acoustically conductive medium into the intracranial space to contact brain tissue of the patient, advancing an ultrasound device at least partially through the aperture in the skull, and transmitting ultrasound energy to the intracranial space, using the ultrasound device. In some embodiments, the acoustically conductive medium may be cooled to help regulate the temperature of the patient's brain tissue.

1 . A system for delivering ultrasound energy to an intracranial space of a patient, the system comprising: 
 an access device having an aperture and configured to be applied to a patient's skull;    an ultrasound device coupled with and extending at least partially through the access device, the ultrasound device including proximal and distal ends;    at least one acoustically conductive medium juxtaposed at the distal end of the ultrasound device; and    means for cooling the acoustically conductive medium to a temperature below at least one of room temperature and body temperature.    
     
     
         2 . The system of  claim 1 , wherein the access device includes a movable positioning member that is coupled to the ultrasound device.  
     
     
         3 . The system of  claim 1 , further comprising a tubular introducer member disposed at least partially within the access device, wherein the ultrasound device is disposed at least partially through the introducer member.  
     
     
         4 . The system of  claim 3 , wherein the introducer member is adapted to allow delivery of the cooled acoustically conductive medium to the brain tissue and around the distal end of the ultrasound device.  
     
     
         5 . The system of  claim 1 , further comprising a tubular introducer member disposed along at least a portion of the ultrasound device to facilitate delivery of the cooled acoustically conductive medium to the brain tissue and around the distal end of the ultrasound device.  
     
     
         6 . The system of  claim 1 , wherein the acoustically conductive medium comprises a fluid that conducts ultrasonic energy.  
     
     
         7 . The system of  claim 1 , further comprising a compliant pack, wherein the acoustically conductive medium is retained within the compliant pack.  
     
     
         8 . The system of  claim 7 , wherein the compliant pack includes a thermal element for changing the temperature of the conductive medium.  
     
     
         9 . The system of  claim 7 , wherein the compliant pack includes at least one of an input port and an output port to facilitate exchange of fluid(s) into and/or out of the pack.  
     
     
         10 . The system of  claim 7 , further comprising at least one thermocouple coupled with the compliant pack.  
     
     
         11 . The system of  claim 1 , wherein the ultrasound device is selected from the group consisting of an ultrasound transducer and a transducer-tipped ultrasound catheter.  
     
     
         12 . The system of  claim 1 , wherein the ultrasound device comprises a diagnostic ultrasound device.  
     
     
         13 . The system of  claim 1 , wherein the ultrasound device comprises a therapeutic ultrasound device.  
     
     
         14 . The system of  claim 1 , wherein the ultrasound device comprises a dual-purpose diagnostic and therapeutic ultrasound device.  
     
     
         15 . The system of  claim 1 , wherein the at least one conductive medium is selected from the group consisting of a condensed gel, a diluted gel, saline, and oil.  
     
     
         16 . A method for delivering ultrasound energy to a patient's intracranial space, the method comprising: 
 forming at least one aperture in the patient's skull;    introducing at least one acoustically conductive medium into the intracranial space to contact brain tissue of the patient;    advancing an ultrasound device at least partially through the aperture in the skull;    cooling the acoustically conductive medium; and    transmitting ultrasound energy to the intracranial space, using the ultrasound device.    
     
     
         17 . The method of  claim 16 , further comprising adjusting the orientation of the ultrasound device with respect to the aperture in the skull.  
     
     
         18 . The method of  claim 16 , further comprising passing a tubular introducer at least partially through the aperture, wherein the ultrasound device is advanced at least partially through the introducer.  
     
     
         19 . The method of  claim 16 , wherein advancing the ultrasound device comprises positioning a distal portion of the ultrasound device such that at least part of the distal portion is surrounded by the acoustically conductive medium.  
     
     
         20 . The method of  claim 16 , wherein introducing the at least one conductive medium comprises introducing the medium intermittently during an intracranial procedure.  
     
     
         21 . The method of  claim 16 , wherein introducing the at least one conductive medium comprises introducing at least a portion of the medium in the epidural space.  
     
     
         22 . The method of  claim 16 , wherein introducing the at least one conductive medium comprises introducing at least a portion of the medium in the aperture.  
     
     
         23 . The method of  claim 16 , wherein introducing the at least one conductive medium comprises introducing at least one material selected from the group consisting of a condensed gel, a diluted gel, saline, and oil.  
     
     
         24 . The method of  claim 16 , further comprising delivering at least one pharmacologic agent to the patient.  
     
     
         25 . The method of  claim 24 , wherein the agent is selected from the group consisting of tissue plasminogen activator, rTPA, Urokinease, Streptokinase, Alteplase, Desmoteplase, aspirin, Clopidorgel, Ticclopidine, Abciximab, Tirofiban and Eptifibatide.  
     
     
         26 . The method of  claim 24 , wherein delivering the agent comprises using a method selected from the group consisting of intravenous, arterial and oral delivery.  
     
     
         27 . The method of  claim 16 , further comprising delivering microbubbles or nanobubbles into the patient's bloodstream.  
     
     
         28 . The method of  claim 16 , further comprising providing a mixture of microbubbles and at least one pharmacological agent to the patient.  
     
     
         29 . The method of  claim 16 , wherein advancing the ultrasound device comprises advancing the device to a location selected from the group consisting of above the aperture, within the aperture, at the edge of the aperture into the patient's epidural space, and into an intracerebral space of the patient's brain.  
     
     
         30 . The method of  claim 16 , wherein introducing the conductive medium comprises introducing the medium to a location selected from the group consisting of above the aperture, within the aperture, at the edge of the aperture, in the patient's epidural space, and in an intracerebral space of the patient's brain.  
     
     
         31 . A method for delivering ultrasound energy to a patient's intracranial space and cooling a patient's brain tissue, the method comprising: 
 forming at least one aperture in the patient's skull;    introducing at least one acoustically conductive medium into the intracranial space to contact brain tissue of the patient;    advancing an ultrasound device at least partially through the aperture in the skull;    cooling at least a portion of the patient's brain tissue; and    transmitting ultrasound energy to the intracranial space, using the ultrasound device.    
     
     
         32 . The method of  claim 31 , wherein cooling the brain tissue comprises cooling the acoustically conductive medium.  
     
     
         33 . The method of  claim 31 , further comprising passing a tubular introducer at least partially through the aperture, wherein the ultrasound device is advanced at least partially through the introducer.  
     
     
         34 . The method of  claim 33 , wherein cooling the brain tissue comprises cooling the tip of the introducer.  
     
     
         35 . The method of  claim 31 , wherein cooling the brain tissue comprises cooling a distal end of the ultrasound transducer.  
     
     
         36 . The method of  claim 31 , wherein cooling the brain tissue comprises cooling the tissue while the ultrasound device is not delivering ultrasound energy.  
     
     
         37 . The method of  claim 31 , further comprising adjusting the orientation of the ultrasound device with respect to the aperture in the skull.